INFLUENCE OF HATCHERY CONDITIONING ON POST-RELEASE SURVIVAL OF JUVENILE COMMON SNOOK Centropomus undecimalis

摘要

Fate of stocked hatchery-reared fish may benefit from prior conditioning during rearing to develop behaviors that enhance survival. In this study we tested whether common snook Centropomus undecimalis can learn certain skills and whether this learningenhances survival of common snook during encounters with predators and competitors in the wild. We exposed hatchery-reared naive juvenile snook to different conditioning treatments: conspecific chemical alarm cue (single exposure, A), structural refuge(S), live food (L), and combinations of the above. After three days of conditioning, juvenile snook were released into a subtropical freshwater lake in southwest Florida and tag detections were monitored over six months using a remote PIT tag antenna tounderstand relative survival of the release groups. Recaptures indicated that the conditioning treatments had a positive effect on post-release survival of the fish. Snook exposed to live food and structure (SL) had the highest recapture rate, followed by those of snook exposed to live food (L) and structure (S) treatments. The alarm cue treatment (A) had the smallest effect on snook recapture rate, but this was improved when combined with treatments of live food and structure. Snook that received no conditioning (control, C) were not detected after 10 days post-release (DPR) by the antenna.